Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Description
WINGED SPROCKET SEGMENTS WITH NOTCHES
Technical Field
The present disclosure relates to a sprocket used to drive a track
chain assembly of an endless undercarriage drive employed by earth moving,
construction and mining equipment and the like. Specifically, the present
disclosure relates to a sprocket that is configured to withstand lateral
thrust
forces, staying centered in a link box of a track chain assembly, and to allow
material to exit the link box so over packing of the material in the link box
is
reduced.
Background
Earth moving, construction and mining equipment and the like are
often used in rough, off-road terrain. These machines often employ an endless
drive with track shoes that is better able to propel the machines in such
environments over obstacles and uneven terrain, etc. The track chain
assemblies,
which include shoes, are held together by a series of interconnected track
links,
pins and bushings that are supported on the drive sprocket, idler and support
rollers of the machine. The drive sprocket, is so called, as it may drive or
convey
power to the track chain assembly, causing it to revolve about the idler
wheels,
resulting in linear motion of the machine.
The drive sprocket includes lugs that fit between various inside
and outside links of the track chain assembly and typically contact a track
chain
bushing that spans between the adjacent inside track links and outside track
links.
As the drive sprocket rotates, a first lug pushes the track chain assembly
along a
direction by pushing on the track chain bushing. Eventually, the first lug
disengages the track chain bushing as a second lug disposed immediately behind
the first lug contacts another track chain bushing, forcing the track chain
assembly to continue to move along the same direction.
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There can be a great deal of lateral force exerted on the sprockets
and material such as mud, sand, dirt, rocks, etc. may infiltrate and cause the
sprocket and the track chain assembly to wear over time. Also, the traction
forces of these machines may lead to excessive wear of the chain links near
the
bushing press fit due to interaction with the sprocket. This wear can affect
the
integrity of the joint. In time, this may cause undesirable maintenance to be
performed on the sprocket or track chain assembly.
U.S. Pat. No. 3,880,478 to Baylor discloses a crawler chain
sprocket that includes a central hub connected to an outer rim on which a
plurality of teeth are formed that engage drive a crawler track. Concave sides
on
the teeth form root face portions between adjacent teeth. Relieved cutouts are
formed on the sides of the root face portions in an alternating pattern so
that dirt
and debris can be expelled from the crawler track without establishing a
concentrated, centralized wear pattern on the crawler track bushings. Baylor
does
not maintain centering of the sprocket in relation to the link box of the
track chain
assembly. So, the track chain assembly in Baylor is prone to undesirable wear
on
the links near where they receive the track bushings.
Summary
An undercarriage assembly according to an embodiment of the
present disclosure may comprise a track chain assembly including a plurality
of
track pins and a plurality of track bushings disposed about the plurality of
track
pins; and a plurality of track links that are connected to each other by at
least one
of the plurality of track pins and the plurality of track bushings. Each of
the
plurality of track links may include a rail portion. The undercarriage
assembly
may further comprise a sprocket member including at least partially a
cylindrical
configuration defining a circumferential direction, a radial direction, and an
axis
of rotation. The sprocket member may include a radially inner portion that
extends in the radial direction and in the axial direction, defining an inner
axial
width of the radially inner portion, and a radially outer portion that extends
in the
axial direction, defining an outer axial width of the radially outer portion.
The
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radially outer portion may also extend along the radial direction, defining an
outer circumferential surface, and a plurality of lugs extending radially from
the
outer circumferential surface. The undercarriage assembly may define a thrust
direction along the axis of rotation, and the sprocket member may include a
first
wing extending from the radially outer portion along the thrust direction. The
sprocket member may define a plurality of notches that extend radially through
the radially outer portion of the sprocket member.
A sprocket segment according to an embodiment of the present
disclosure may comprise a body including at least partially a cylindrical
.. configuration defining a circumferential direction, a radial direction, and
an axis
of rotation. The body may also include a radially inner portion that extends
in the
radial direction and in the axial direction, the radially inner portion
defining an
inner axial width of the radially inner portion, and an inner radial height of
the
radially inner portion. The radially inner portion may further define a
plurality of
fastener receiving holes extending axially through the radially inner portion.
The
body may also include a radially outer portion that extends along the axial
direction and the radial direction, defining an outer axial width of the
radially
outer portion, and an outer radial height of the radially outer portion. The
outer
axial width of the radially outer portion may be greater than the inner axial
width
.. of the radially inner portion, while the radially outer portion may also
include an
outer undulating circumferential surface. The radially outer portion may
further
define an inner cylindrical circumferential bearing surface disposed axially
on
one side of the radially inner portion, and a first wing extending axially
from the
radially outer portion that is disposed radially and axially adjacent to the
inner
cylindrical circumferential bearing surface. The first wing may define a first
wing radial height that is less than the outer radial height of the radially
outer
portion. The radially outer portion may also define a plurality of cut-outs
extending radially through the radially outer portion disposed axially on the
other
side of the radially inner portion relative to the first wing.
A sprocket segment according to another embodiment of the
present disclosure may comprise a body including at least partially a
cylindrical
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configuration defining a circumferential direction, a radial direction, and an
axis
of rotation. The body may include a radially inner portion that extends in the
radial direction and in the axial direction, the radially inner portion
defining an
inner axial width of the radially inner portion, and an inner radial height of
the
radially inner portion. The radially inner portion may further define a
plurality of
fastener receiving holes extending axially through the radially inner portion.
The
body may also include a radially outer portion that extends along the axial
direction and the radial direction, defining an outer axial width of the
radially
outer portion, and an outer radial height of the radially outer portion. The
outer
axial width of the radially outer portion may be greater than the inner axial
width
of the radially inner portion, and may include an outer undulating
circumferential
surface. The radially outer portion may further define an inner cylindrical
circumferential bearing surface disposed axially on one side of the radially
inner
portion, and a first wing extending axially from the radially outer portion
that is
disposed radially and axially adjacent to the inner cylindrical
circumferential
bearing surface. The first wing may define a first wing radial height that is
less
than the outer radial height of the radially outer portion. The body may also
include a second wing extending axially from the radially outer portion on
another side axially of the radially inner portion opposite of the first wing.
The
second wing may also define a second wing radial height that is less than the
outer radial height of the radially outer portion. The radially outer portion
may
also define a plurality of notches extending radially through the radially
outer
portion. At least one of the plurality of notches may extend through the first
wing and at least another of the plurality of notches may extend through the
second wing.
Brief Description of the Drawings
The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate several embodiments of the
disclosure and together with the description, serve to explain the principles
of the
disclosure. In the drawings:
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FIG. 1 is a side-view of a machine such a hydraulic mining shovel
that may use sprockets with winged sprocket segments with notches according to
various embodiments of the present disclosure.
FIG. 2 is a front oriented perspective view of a winged sprocket
segment with notches mating with a track chain assembly that may be used in
the
undercarriage assembly of the machine of FIG. 1 according to a first
embodiment
of the present disclosure.
FIG. 3 is a top view of the winged sprocket segment with notches
and the track chain assembly of FIG. 2.
FIG. 4 is a rear oriented perspective view of the winged sprocket
segment with notches and the track chain assembly of FIG. 2.
FIG. 5 is a front oriented perspective view of the winged sprocket
segment with notches of FIG. 2 shown in isolation from the track chain
assembly.
FIG. 6 is a rear oriented perspective view of the winged sprocket
segment with notches of FIG. 4 shown in isolation from the track chain
assembly.
FIG. 7 is a front oriented perspective view of a winged sprocket
segment with notches mating with a track chain assembly that may be used in
the
undercarriage assembly of the machine of FIG. 1 according to a second
embodiment of the present disclosure.
FIG. 8 is a top view of the winged sprocket segment with notches
and the track chain assembly of FIG. 7.
FIG. 9 s a rear oriented perspective view of the winged sprocket
segment with notches and the track chain assembly of FIG. 7.
FIG. 10 is a front oriented perspective view of the winged
sprocket segment with notches of FIG. 7 shown in isolation from the track
chain
assembly.
FIG. 11 is a rear oriented perspective view of the winged sprocket
segment with notches of FIG. 9 shown in isolation from the track chain
assembly.
FIG. 12 is a rear oriented perspective view of a winged sprocket
segment with notches mating with a track chain assembly that may be used in
the
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undercarriage assembly of the machine of FIG. 1 according to a third
embodiment of the present disclosure.
FIG. 13 is a top view of the winged sprocket segment with notches
and the track chain assembly of FIG. 12.
FIG. 14 is a rear oriented perspective view of the winged sprocket
segment with notches of FIG. 12 shown in isolation from the track chain
assembly.
Detailed Description
Reference will now be made in detail to embodiments of the
disclosure, examples of which are illustrated in the accompanying drawings.
Wherever possible, the same reference numbers will be used throughout the
drawings to refer to the same or like parts. In some cases, a reference number
will be indicated in this specification and the drawings will show the
reference
number followed by a letter for example, 100a, 100b or by a prime for example,
100', 100" etc. It is to be understood that the use of letters or primes
immediately after a reference number indicates that these features are
similarly
shaped and have similar function as is often the case when geometry is
mirrored
about a plane of symmetry. For ease of explanation in this specification,
letters
and primes will often not be included herein but may be shown in the drawings
to
indicate duplications of features, having similar or identical function or
geometry,
discussed within this written specification.
An undercarriage assembly that may use a sprocket member or a
sprocket segment according to various embodiments of the present disclosure
will now be described. In some embodiments, the sprocket member is a complete
sprocket wheel (e.g. having unitary construction). In other embodiments, the
sprocket member is a sprocket segment that is attached to a hub to form the
drive
sprocket wheel assembly, etc. Other configurations for the sprocket member are
possible in other embodiments of the present disclosure.
FIG. 1 shows an embodiment of a tracked machine 100 in the
form of a hydraulic mining shovel that includes an embodiment of an
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undercarriage assembly 200 constructed in accordance with principles of the
present disclosure. Among other uses, a hydraulic mining shovel can be used to
load overburden and ore into haul trucks during the mining process in various
surface mine applications.
While the arrangement is illustrated in connection with a hydraulic
mining shovel, the arrangement disclosed herein has universal applicability in
various other types of machines commonly employ track systems, as opposed to
wheels. The term "machine" may refer to any machine that performs some type
of operation associated with an industry such as mining, earth moving or
construction, or any other industry known in the art. For example, the machine
may be an excavator, a wheel loader, a cable shovel, a track type tractor, a
dozer,
or dragline or the like. Moreover, one or more implements may be connected to
the machine. Such implements may be utilized for a variety of tasks,
including,
for example, lifting and loading.
As shown in FIG. 1, the machine 100 may include a body 104,
with a track system 102 attached thereto, and also has a cab 106 to house a
machine operator. The machine may also include a boom system 108 pivotally
connected at one end to the body 104 and supporting an implement 110 at an
opposing, distal end. In embodiments, the implement 110 can be any suitable
implement, such as a bucket, a clamshell, a blade, or any other type of
suitable
device. A control system can be housed in the cab 106 that can be adapted to
allow a machine operator to manipulate and articulate the implement 110 for
digging, excavating, or any other suitable application.
The body 104 may be supported on a main frame 112 connected to
an undercarriage assembly 200. The undercarriage structure 114 includes a
supporting structure 118 that supports the track system 102 utilized for
movement
of the machine 100. The track system 102 may include first and second track
roller frame assemblies 116, which are spaced from and adjacent respective
first
and second sides of the undercarriage assembly 200. It will be appreciated
that
only one of the track roller frame assemblies 116 is visible in FIG. 1.
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Each of the track roller frame assemblies 116 carries an idler
wheel 120, a drive sprocket assembly 122, and a plurality of track guiding
rollers
124. The drive sprocket assembly 122, is powered in forward and reverse
directions by the machine 100. An endless track chain assembly 126 encircles
each drive sprocket assembly 122, the idler wheel 128, and the track guiding
rollers 124. The track chain assembly 126 includes a plurality of
interconnected
track pads 128. The track guiding rollers 124 guide the track pads 128 as the
track chain assembly 126 is driven by the drive sprocket wheel assembly 122.
The track chain assembly 126 may have any track chain member, track pin
retention device, and/or track chain assembly. A power source 130 supplies the
power to drive the track chain assembly 126 via the sprocket assembly 122, as
the
lugs 302, 402, 502 of the drive sprocket assembly 122 engage the various track
bushings (not shown in FIG. 1), propelling the movement of the track chain
assembly 126 as described earlier herein.
Power source 102 may drive undercarriage assembly 200 of
machine 100 at a range of output speeds and torques. Power source 102 may be
an engine such as, for example, a diesel engine, a gasoline engine, a gaseous
fuel-
powered engine, or any other suitable engine. Power source 102 may also be a
non-combustion source of power such as, for example, a fuel cell, a power
storage device, or any other source of power known or that will be devised in
the
art.
For example, as shown in FIG. 1, the sprocket assembly 112 may
comprise a hub 202 that is connected to a drive axle (not shown) of the
machine
100 and a sprocket segment 300', 400', 500' (not clearly shown in FIG. 1) that
is
attached via fasteners, welding, adhesives, etc. to the radial outer edge of
the hub
202. This sprocket segment 300', 400', 500' may form the lugs 302, 402, 502
that help to propel the track chain assembly 126.
Referring now at FIGS. 2 thru 14, various embodiments of an
undercarriage assembly 200 that may use sprocket members 300, 400, 500 (e.g.
sprocket segments 300', 400', 500') according to various embodiments of the
present disclosure will now be discussed in detail.
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In FIGS. 2 thru 4, 7 thru 9, 12, and 13, an undercarriage assembly
200 according to an embodiment of the present disclosure may comprise a track
chain assembly 126 including a plurality of track pins 202, a plurality of
track
bushings 204 disposed about the plurality of track pins 202, and a plurality
of
track links 206 that are connected to each other by at least one of the
plurality of
track pins 202 and the plurality of track bushings 204. Each of the plurality
of
track links 206 includes a rail portion 206a for supporting the weight of the
machine 100 by mating with the rollers 124, and idler wheel 120 as best seen
in
FIG. 1.
With continued reference to FIGS. 2 thru 4, 7 thru 9, 12, and 13,
the sprocket member 300, 400, 500 may include at least partially a cylindrical
configuration defining a circumferential direction 304, 404, 504, a radial
direction 306, 406, 506, and an axis of rotation 308, 408, 508. The sprocket
member 300, 400, 500 may include a radially inner portion 310, 410, 510 that
extends in the radial direction 306, 406, 506, and in the axial direction
(i.e. along
axis of rotation 308, 408, 508), defining an inner axial width 312, 412, 512
of the
radially inner portion 310, 410, 510. The sprocket member 300, 400, 500 may
also include a radially outer portion 314, 414, 514 that extends in the axial
direction 300, 400, 500 (i.e. along axis of rotation 308, 408, 508), defining
an
outer axial width 316, 416, 516 of the radially outer portion 314, 414, 514.
The
radially outer portion 314, 414, 514 may also extend along the radial
direction
306, 406, 506, defining or terminating in an outer circumferential surface
318,
418, 518, a plurality of lugs 302, 402, 502 (as previously mentioned herein)
may
be attached to or may otherwise extend radially from the outer circumferential
surface 318, 418, 518.
The undercarriage assembly 200 may define a thrust direction 208
along the axis of rotation 308, 408, 508 toward the center or interior of the
machine 100.
With continued reference to FIGS. 2 thru 4, 7 thru 9, 12, and 13,
the sprocket member may include a first wing 320, 420, 520 extending from the
radially outer portion 314, 414, 514 along the thrust direction 208. Moreover,
the
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sprocket member 300, 400, 500 may define a plurality of notches 322, 422, 522
that extend radially through the radially outer portion 314, 414, 514 of the
sprocket member 300, 400, 500. The outer axial width 316, 416, 516 of the
radially outer portion 314, 414, 514 may be greater than the inner axial width
312, 412, 512 of the radially inner portion 310, 410, 510, as shown in the
figures,
but not necessarily so.
Also, each of the plurality of track links 206 may be an offset
track link 206' (e.g. the body of the track link jogs, producing an "s" shape)
as
shown in the figures or may be straight (e.g. the body of the track link is
shaped
more like a "t"), etc. In addition, each of the plurality of track links 206
may
include a web 206b extending downwardly from the rail portion 206a, forming a
T-shaped configuration.
As best seen in FIGS. 2, 4, 7, 9, and 12, each of the plurality of
track links 206 may receive at least one of the plurality track bushings 204,
forming a track link and track bushing interface 210. Each track link and
track
bushing interface 210 may include a press-fit between the track bushing 204
and
the track link 206, forming the track link and track bushing interface 210.
Other
types of interfaces are possible in other embodiments of the present
disclosure
including slip fits or other types of attachment including using fasteners,
welding,
adhesives, etc.
Looking at FIGS. 4, 9, and 12, the first wing 320, 420, 520 may be
configured to contact the rail portion 206a, spacing the plurality of lugs
302, 402,
502 of the sprocket member 300, 400, 500 axially away from the track link and
track bushing interface 210 a clearance distance 212 ranging from 0 mm to 20
mm. Other values for this clearance distance are possible in other embodiments
of the present disclosure.
As alluded to earlier herein, the sprocket member 300, 400, 500
may be made from a single piece of material or may be part of an assembly such
as when a sprocket segment 300', 400', 500' is attached to a hub to form the
drive sprocket, etc.
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Referring now to FIGS. 5 and 6, the sprocket segment 300' may
define a radially inner portion axial midplane 324, and a radially outer
portion
axial midplane 326 that is offset axially from the radially inner portion
axial
midplane 324. The plurality of notches 322 extends solely through the radially
outer portion 314 on a side of the radially outer portion axial midplane 326
that is
axially opposite of the first wing 320.
On the other hand, as shown by FIGS. 10, 11, and 14, the sprocket
segment 400', 500' defines a radially inner portion axial midplane 424, 524,
and
a radially outer portion axial midplane 426, 526 that is offset axially from
the
radially inner portion axial midplane 424, 524. The sprocket segment 400',
500'
may also include a second wing 428, 528 (528 is best seen in FIG. 13)
extending
axially away from the radially outer portion 414, 514 on another side of the
radially outer portion axial midplane 426, 526 that is axially opposite of the
first
wing 420, 520. For these embodiments, the plurality of notches 422, 522 extend
through both the first wing 420, 520 and the second wing 428, 528 of the
radially
outer portion 414, 514 of the sprocket segment 400', 500'.
In FIGS. 8, 10, and 11, the plurality of notches 422 defines an
alternating pattern with one of the plurality of notches 422 on the first wing
420,
520 being spaced circumferentially away from the adjacent one of the plurality
of
notches 422, 522 on the second wing 428, 528.
Referring again to FIGS. 5 and 6, a sprocket segment 300'
according to a first embodiment of the present disclosure that may be provided
as
a replacement part will now be described by itself
The sprocket segment 300' may comprise a body 300a including
at least partially a cylindrical configuration defining a circumferential
direction
304, a radial direction 306, and an axis of rotation 308 as previously alluded
to
herein.
The body 300a may include a radially inner portion 310 that
extends in the radial direction 306 and in the axial direction (i.e. along the
axis of
rotation 308). The radially inner portion 310 may define an inner axial width
312
of the radially inner portion 310, and an inner radial height 312' of the
radially
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inner portion 310. The radially inner portion 310 further defining a plurality
of
fastener receiving holes 330 extending axially through the radially inner
portion
310 so that the sprocket segment 300' may be attached to a hub to form the
drive
sprocket.
The body 300a may also include a radially outer portion 314 that
extends along the axial direction and the radial direction 306, defining an
outer
axial width 316 of the radially outer portion 314, and an outer radial height
316'
of the radially outer portion 314. The outer axial width 316 of the radially
outer
portion 314 is greater than the inner axial width 312 of the radially inner
portion
310. The radially outer portion 314 may also include an outer undulating
circumferential surface 318'.
The radially outer portion 314 further defines an inner cylindrical
circumferential bearing surface 332 disposed axially on one side of the
radially
inner portion 310, and a first wing 320 extending axially from the radially
outer
portion 314 that is disposed radially and axially adjacent to the inner
cylindrical
circumferential bearing surface 332. The first wing 320 may define a first
wing
radial height 320a that is less than the outer radial height 316' of the
radially
outer portion 314. The radially outer portion 314 also may define a plurality
of
cut-outs 322' extending radially through the radially outer portion 314
disposed
axially on the other side of the radially inner portion 310 relative to the
first wing
320.
As alluded to earlier herein, the sprocket segment 300' defines a
radially inner portion axial midplane 324, and a radially outer portion axial
midplane 326 that is offset axially from the radially inner portion axial
midplane
324, thus providing a suitably sized inner cylindrical circumferential bearing
surface 332. The outer undulating circumferential surface 318' of the radially
outer portion 314 may define the plurality of lugs 302.
Each of the plurality of fastener receiving holes 330 may be
disposed in radial alignment with each of the plurality of lugs 302 but not
necessarily so. Similarly, each of the plurality of cut-outs 322' may be
disposed
circumferentially between each of the plurality of lugs 302 but not
necessarily so.
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At least two keys 334 may extend axially and radially inwardly
from the inner cylindrical circumferential bearing surface 332. So, when the
sprocket segment 300' is attached to the hub, the inner cylindrical bearing
surface
332 may be supported by the outer radial surface of the hub while the keys 334
fit
into pockets or recesses located on the outer radial surface of the hub.
Hence, as
the hub is driven to rotate, so is the sprocket segment 300'.
With continued reference to FIGS. 5 and 6, the plurality of cut-
outs 322' may define a maximum circumferential cut-out distance 336 measured
in the circumferential direction 304 ranging from 15 mm to 175 mm (may be
10% to 50% of the pitch length), and a maximum axial cut-out depth 338
measured along the axial direction 306 ranging from 1 mm to 75 mm (may be 1%
to 50% of the sprocket width). The first wing 320 may define a first wing
axial
width 320b ranging from 0 mm to 20 mm, while the first wing radial height 320a
may range from 1 mm to 50 mm. Any of these features may be differently
shaped or dimensioned in other embodiments of the present disclosure.
Focusing now on FIGS. 10, 11, 13 and 14, a sprocket segment
400', 500' according to a second embodiment, and a third embodiment of the
present disclosure that may be provided as a replacement part will now be
described by themselves.
The sprocket segment 400', 500' may comprise a body 400a, 500a
including at least partially a cylindrical configuration defining a
circumferential
direction 404, 504, a radial direction 406, 506, and an axis of rotation 408,
508.
The body 400a, 500a may include a radially inner portion 410, 510 that extends
in the radial direction 406, 506, and in the axial direction (i.e. along the
axis of
rotation 408, 508). The radially inner portion 410, 510 may define an inner
axial
width 412, 512 of the radially inner portion 410, 510, and an inner radial
height
412', 512' of the radially inner portion 410, 510. Also, the radially inner
portion
410, 510 may further define a plurality of fastener receiving holes 430, 530
extending axially through the radially inner portion 410, 510.
The body 400a, 500a may also include a radially outer portion
414, 514 that extends along the axial direction, and the radial direction 406,
506,
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defining an outer axial width 416, 516 of the radially outer portion 414, 514,
and
an outer radial height 416', 516' of the radially outer portion 414, 514. The
outer
axial width 416, 516 of the radially outer portion 414, 514 is greater than
the
inner axial width 412, 512 of the radially inner portion 410, 510, and
includes an
outer undulating circumferential surface 418', 518'.
In addition, the radially outer portion 414, 514 further defines an
inner cylindrical circumferential bearing surface 432, 532 disposed axially on
one
side of the radially inner portion 410, 510, and a first wing 420, 520
extending
axially from the radially outer portion 414, 514 that is disposed radially and
axially adjacent to the inner cylindrical circumferential bearing surface 432,
532.
The first wing 420, 520 defines a first wing radial height 420a, 520a that is
less
than the outer radial height 416', 516' of the radially outer portion 414,
514.
A second wing 428, 528 may be provided that extends axially
from the radially outer portion 414, 514 on another side axially of the
radially
inner portion 410, 510 opposite of the first wing 420, 520. The second wing
428,
528 also defines a second wing radial height 428a, 528a that is less than the
outer
radial height 416', 516' of the radially outer portion 414, 514. The radially
outer
portion 414, 514 may also define a plurality of notches 422, 522 extending
radially through the radially outer portion 414, 514. At least one of the
plurality
of notches 422, 522 extends through the first wing 420, 520 and at least
another
of the plurality of notches 422, 522 extending through the second wing 428,
528.
In FIGS. 10 and 11, the plurality of notches 422 defines an
alternating circumferential pattern with one of the plurality of notches 422
on the
first wing 420 being spaced circumferentially away from the adjacent one of
the
plurality of notches 422 on the second wing 428.
Conversely, in FIGS. 13 and 14, the plurality of notches 522
includes defines a synchronized circumferential pattern with one of the
plurality
of notches 522 on the first wing 520 being circumferentially aligned with the
adjacent one of the plurality of notches 522 on the second wing 528.
In FIGS. 10, 11, 13, and 14, at least two keys 434, 534 may extend
axially and radially inwardly from the inner cylindrical circumferential
bearing
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surface 432, 532. So, when the sprocket segment 400', 500' is attached to the
hub, the inner cylindrical bearing surface 432, 532 may be supported by the
outer
radial surface of the hub while the keys 434, 534 fit into pockets or recesses
located on the outer radial surface of the hub. Hence, as the hub is driven to
rotate, so is the sprocket segment 400', 500'.
For the embodiments shown in FIGS. 10, 11, 13, and 14, each of
the plurality of notches 422, 522 defines a maximum circumferential notch
distance 436, 536 measured in the circumferential direction 404, 504 ranging
from 15 mm to 175 mm, and a maximum axial notch depth 438, 538 measured
along the axial direction ranging from 1 mm to 75 mm. The first wing 420, 520
may define a first wing axial width 420b, 520b ranging from 0 mm to 20 mm,
and the first wing radial height 420a, 520a may range from 1 mm to 50 mm.
Likewise, the second wing 428, 528 may define a second wing axial width 428b,
528b ranging from 0 mm to 20 mm, and the second wing radial height 428a, 528a
may range from 1 mm to 50 mm. Any of these features may be differently
shaped or dimensioned in other embodiments of the present disclosure.
For many embodiments, the sprocket member may be cast using
iron, grey-iron, steel or other suitable materials. The sprocket member may be
split into multiple parts that may also be split into multiple parts. For
example,
the lugs by be attached to the sprocket segment. The lugs may also be cast
using
iron, grey-iron, steel or other suitable materials. The lug may be made from a
different material than the sprocket member. Since the lugs are smaller than
the
sprocket member, a material may be used to form the lugs that is difficult to
use
in larger castings. Other manufacturing processes may be used to make the lugs
such as any type of machining, forging, etc. For example, steel or "tough
steel"
may be used to create the lugs. Lugs may also be coated, heat treated, etc. to
provide suitable characteristics for various applications.
Industrial Applicability
In practice, a sprocket assembly, a sprocket member, a sprocket
segment, and an undercarriage assembly according to any embodiment described
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herein may be sold, bought, manufactured or otherwise obtained in an OEM or
after-market context.
The various embodiments of the sprocket member may keep the
sprocket centered within the link box while the notches or cut-outs may help
mud, dirt, or other material to move out of the link box formed by two track
bushings and two track links that form a rectangular shaped perimeter. The
spacing provided by the wings of the sprocket member may help to reduce wear
on the track links near a track bushing and track link interface such as a
press-fit
connection.
It will be apparent to those skilled in the art that various
modifications and variations can be made to the embodiments of the apparatus
and methods of assembly as discussed herein without departing from the scope
or
spirit of the invention(s). Other embodiments of this disclosure will be
apparent
to those skilled in the art from consideration of the specification and
practice of
the various embodiments disclosed herein. For example, some of the equipment
may be constructed and function differently than what has been described
herein
and certain steps of any method may be omitted, performed in an order that is
different than what has been specifically mentioned or in some cases performed
simultaneously or in sub-steps. Furthermore, variations or modifications to
certain aspects or features of various embodiments may be made to create
further
embodiments and features and aspects of various embodiments may be added to
or substituted for other features or aspects of other embodiments in order to
provide still further embodiments.
Accordingly, it is intended that the specification and examples be
considered as exemplary only, with a true scope and spirit of the invention(s)
being indicated by the following claims and their equivalents.
